According to new research, both men and women give up on self-treatment after within four to seven days of experiencing cold symptoms, but if the illness is viral, visiting the doctor will do no good and antibiotics won’t be of any use.

Dr Maureen Baker, health protection spokesperson for the Royal College of GPs, explains: "When it's a purely viral illness like most colds, flu, the winter vomiting bug and chicken pox, antibiotics will have no effect whatsoever.”

But viral winter illnesses can often last longer than most people expect, though it’s quite rare for them to develop into anything more serious or to come down with a bacterial infection on top.

"That's not the common course of the illness," stresses Dr Baker. "The vast majority of people with a viral illness will have no bacterial complications."

The research by Men's Health Forum found that for men, and a little surprisingly women too, lingering symptoms for more than a few days are all it takes to send us straight to the GP, begging for antibiotics.

But symptoms of viruses can linger for some time, even when the virus has been beaten by your immune system. According to the National Institute for Health and Clinical Excellence (NICE), a cough can last as long as three weeks, sinusitis can last two and a half, and a cold can linger for up to a week and a half.What should you do if you’ve been feeling rotten for ages?

Dr Baker recommends the NHS website for guidelines or you can ask your pharmacist for advice.

Leyla Hannbeck, head of pharmacy at the National Pharmacy Association, says: "Some people research their symptoms on the internet and believe whatever they read and start self-treating, which isn't the best way of doing things."

At home guidelines for coughs, colds, sore throats, flu and vomiting bugs

Colds

Typical symptoms include a blocked or runny nose, sneezing, irritated throat, cough, headache and general feeling of being run-down. Colds usually last four or five days but, like most viruses, occasionally they'll linger for a week or two. When the viral infection has settled, symptoms such as a cough or feeling congested may last for several weeks.

"In general, there's no need to consult a doctor unless people think they're becoming worse rather than better or develop new or worrying symptoms, like coughing up blood," says Baker.

More than 90 per cent of sore throats (pharyngitis or tonsillitis) are caused by viral infections and don't respond to antibiotics or other medication, says DrBaker, who advises that patients should rest, drink plenty of fluids and try throat sweets or hot drinks with honey and lemon.

Many people mistake a bad cold for flu. However, as well as cold symptoms, flu typically also entails a sudden fever/high temperature, loss of appetite, sometimes nausea, general weakness and aching. People with flu may feel extremely unwell and unable to get out of bed.

Most people who have flu will begin to feel better after a few days, but some will react very badly to the virus.

"If after two or three days people are starting to get worse rather than better, that's when it would be reasonable to get checked by a doctor," advises Dr Baker. "What we worry about is bacterial or viral pneumonia."

The majority of coughs, though they can sound awful and are extremely annoying to have, are not serious. However, a cough can persist for as long as three weeks - because although the infection may have gone, there could still be inflammation, or airways may have become irritated.

Coughs that get worse, rather than better, and any accompanied by a tight chest or blood should be checked out by a GP.